Low insertion force electrical connector

ABSTRACT

A low insertion force connector having a pair of connector members each with a plurality of contacts therein. One of the connector members is formed of a stationary insulator and an activating disc, the activating disc being formed with a cammed surface. The insulator has a plurality of axially alined bores with contacts mounted therein. A shell member has a cam actuating member therein with rotation of the shell member causing the cam actuating member to move with respect to the activating disc and to move the activating disc with respect to the axis of the bores and coupling the contacts in the connector members together. An interlock may be formed on the shell member for allowing the connector members to be correctly positioned prior to electrically connecting the contacts together. Further, a sealing device may be formed between the shell member and the electrical connector member on which it is mounted. Moreover, a novel grommet provides a tight seal at the rear of the connector members. Also, a cable clamp ring is removably secured to the rear of the connector members for attachment to the cable conductors.

United States Patent [191 Barr [ LOW INSERTION FORCE ELECTRICAL CONNECTOR [75] Inventor: John E. Barr, Van Nuys, Calif.

[73] Assignee: International Telephone and Telegraph Corporation, New York, NY.

[22] Filed: Dec. 7, 1970 [21] Appl. No.: 95,755

Primary ExaminerJoseph HQ McGlynn Attorney, Agent, or Firm-Thomas L. Peterson June 18, 1974 5 7 ABSTRACT A low insertion force connector having a pair of connector members each with a plurality of contacts therein. One of the connector members is formed of a stationary insulator and an activating disc, the activating disc being formed with a cammed surface. The insulator has a plurality of axially alined bores with contacts mounted therein. A shell member has a cam actuating member therein with rotation of the shell member causing the cam actuating member to move with respect to the activating disc and to move the activating disc with respect to the axis of the bores and coupling the contacts in the connector members together. An interlock may be formed on the shell member for allowing the connector members to be correctly positioned prior to electrically connecting the contacts together. Further, a sealing device may be formed between the shell member and the electrical connector member on which it is mounted. Moreover, a novel grommet provides a tight seal at the rear of the connector members. Also, a cable clamp ring is removably secured to the rear of the connector members for attachment to the cable conductors.

8 Claims, 17 Drawing Figures PMENTEUJUM 8 m4 SHEET 1 0r 4 PATENTEU 81974 SHEET 2 BF 4 INVENTQR. JOHN E. 5

PATENTEDJUM 8 W 3.8 1 8.420

SHEU l 0? 4 INVENTQR.

BY M7 Kg flrroe/vev v1 LOWINSERTION FORCE ELECTRICAL CONNECTOR BACKGROUND OF THE INVENTION Conventional low insertion force connectors normally utilize a movable insulator member to couple a pair of electrical contacts in the electrical connector subsequent to mating of the electrical connectors. These electrical connectors typically require an external tool which is inserted into a movable member, actuation of the movable member causing the insulator member or members to move, in turn causing the contacts to be electrically connected to each other. These connectors are typically of rectangular cross section and movement of the actuating plug is in a plane perpendicular to the axis of the connector. These simple designs cannot be readily accommodated when the electrical connector is utilized in a circular connector. For example, the degree of movement necessary in a circular plug as compared to a rectangular connector is of such size that unless a low density arrangement, that is, a small number of contacts for a given envelope is utilized, movement of the movable insulator plug would be outside of the periphery of the connector member. I

In order to overcome the attendant disadvantages of prior art zero force electrical connector members, the present invention incorporates an internal actuating arrangement wherein rotation of one of the connector member elements causes the proper movement of the actuating plate. Further, since a small portion of the connector shell is utilized for coupling, higher density contact arrangements are possible.

The advantages of this invention, both as to its construction and mode of operation will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings in which like reference numerals designate like parts throughout the figures.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 depicts an elevational view of a plug and receptacle connector member utilized in accordance with the invention;

FIG. 2 illustrates an exploded perspective view of a plug connector member incorporating the principles of the invention;

FIG. 3 shows an exploded perspective view of the receptacle connector member incorporating the principles of the invention;

FIG. 4 depicts a partial sectional view of the plug connector of FIG. 2;

FIG. 5 illustrates a partial sectional view of the receptacle connector depicted in FIG. 3;

FIG. 6 (a-c) show various stages of movement of the contacts during the contact engagement process;

FIGS. 7 (11-0) depict the movement of the coupling ring in a position comparable to the contacts of FIGS. 6 (a-c), respectively;

FIGS. 8 and 9 illustrate partial sectional views of the plug and receptacle connectors and the grommet mounting therein;

2 FIGS. 10 and 11 show portions of the polarizing 'means utilized inthe sealing grommet of the connector members, and

FIGS. 12 and 13 depict the boot utilized with the connector members of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings, there is shown a mating pair of connector members formed of a plug connector l2and a receptacle connector 14. The plug connector, which is shown in exploded detail in FIG. 2, has

external portion of the stationary insulator 22 is a cable clamp ring 26. Mounted on the cable clamp ring is an environmental boot 28. Further positioned within the insulator member 22 are a plurality of contacts 32 having secured at the rear end thereof wire conductors 34.

The receptacle connector member shown in ex- .ploded detail in FIG. 3 is formed of an insulator mem ber 52 having a grommet 54 which may be identical to the grommet 24 mountable within the rear end of the insulator member 52. A cable clamp ring 56 and a boot 58 are mounted on the rear end of the insulator 52 in a similar manner as the clamp ring 26 and boot 28 of the plug connector. It should be noted that the grommets 24 and 54, as well as the cable clamp rings 26 and 56 and boots 28 and 58 are made identically for both the plug and receptacle connector so as to minimize the number of parts utilized in the system, although such an interchangeable feature does not form a part of the invention. Finally, a plurality of contacts 62 having wire conductors 64 secured to the rear end thereof are mounted within the insulator member 52 and can also be made identically to the contacts 32 in the plug connector.

In FIG. 4 there is shown a partial cross sectional view of the plug connector, with the grommet 24 removed to facilitate explanation of the details thereof. The coupling ring 16 is typically knurled at the rear outer surface 65 and may contain a raised portion 66 along the surface 65 for use as a position indicator during mating. An inwardly extending flange member 68 is formed at the rear end of the coupling ring. A tapered bore surface 72 extends from a forward facing shoulder 74 of the flange 68 to a rear enlarged bore surface 76. An intermediate bore portion 78 in the coupling ring terminates at its rear end at a rearward facing shoulder 82 and at the front end at a rearward facing shoulder 84. The front inner surface of the coupling ring contains a bore surface 86 extending from the shoulder 84 to a forward facing shoulder 88. A small enlarged bore 92 is formed at the front end of the coupling ring and terminates at the forward facing shoulder 88. A radial groove 94 is cut into the front surface 96 of the coupling ring with a small portion of insulating material 98 remaining between the bore 92 and the groove 94.

As can be seen in FIG. 2, the coupling ring has formed on the bore surface 86 a first coupling tooth 102 and a second coupling tooth 104. The teeth 102 and 104 are approximately apart. The teeth 102 and 104 are typically trapezoidal with the larger base being formed internal with the bore surface 86. Further, a pair of driver teeth 106 and 108 are formed on the bore surface 78 with approximately a 120 spacing.

The actuating disc 18 contains a front surface 112 and a rear surface 114. Extending forwardly from the front surface 112 are a pair of polarizing keys 116 and 118 and extending rearwardly from the surface 114 is an anti-rotation tongue 122. Further, a groove 124 is cut into the rear surface of the actuating member and operates in combination with the tongue 122 to mate with a similar tongue and grooving arrangement in the stationary insulator 22 as will be explained hereinafter. A plurality of bores 126 are formed in the insulator 18 for positioning of the contacts 32 therein. The outer side walls of the disc 18 form a cam surface.

As shown in greater detail in FIGS. 7 (a-c) the cam surface is formed of a first flat portion 132. From the ends of the flat portion 132 the cam surface decreases radially from the center of the disc as at 134 until a shoulder surface 136 is reached which defines the end of the decreasing radial surface 134. The other side of the cam surface 137 has a constant radius and then starts to radially decrease until it reaches a shoulder surface 138. The ends of the shoulder surfaces are joined together by a surface 142.

The stationary insulator 22 has a front surface 202 having a tongue 204 and groove 206 arrangement which allows the stationary insulator to be locked to the actuating disc so as to prevent rotation of the disc 18 with respect to the stationary insulator 22. The front half of the insulator 22 contains a plurality of bores 208 which are axially alined with the bores 126 and contain a flange member 212 having a forward facing shoulder 214 and a rearward facing shoulder 216. The rear inner surface of the insulator 22 is formed of a bore surface 217 with a tapered flared rear end 218 and a rearward facing shoulder 222 defining the front end of the bore 217. Further, a plurality of openings 224 in the center of the bore surface 217 extend to the outer surface of the insulator 22. The outer surface of the insulator 22 has a gradual outward flared portion 232 which terminates at a groove 234 formed in the center of the outer surface of the insulator. At the rear end of the groove and integral with the insulator is a radially extending flange 236. The flange member 68 of the coupling ring 16 is mounted in the groove 234 and forms a seal with the flange 236. The outer surface 238 defines the rear central portion of the stationary insulator 22 with the openings 224 in the insulator 22 extending to the surface 238. The rear outer surface rearward of the sur face 238 is notched to form a plurality of openings 244 and coupling teeth 246 adjacent each other. Further, the stationary insulator contains a polarizing key 248 shown in greater detail in FIG. 11 extending from the rearward facing shoulder 222.

The wire seal grommet 24 is typically made of rubber and contains a front face 252. The front surface of the grommet 252 may contain a keyway 254 for correctly positioning the grommet with respect to the insulator 22 by inserting the key 248 therein. The grommet contains a plurality of bores 256 which are axially alined with the bores 126 and 208. Each of the bores 256 may terminate at the rear end of the grommet in a thin membrane surface 258 which can be punctured easily. and if not punctured, provides an environmental seal.

The outer surface of the grommet is slightly smaller in diameter than the bore 217 of the insulator 22 and contains a pair of outwardly extending flange surfaces 262 and 264 whose outer edge defines a diameter slightly larger than the diameter of surface 217 and which provide an environmental seal with the bore surface. F urther formed on the outer surface of the grommet are a plurality of outwardly extending members 266 which, when the grommet is inserted in the rear end of the insulator, protrude into the openings 224 in the insulator 22 so as to form a tight fit of the grommet in the insulator and retain the grommet therein.

The cable clamp ring 26 is formed of a cylindrical member 272 having a plurality of tongues 274 and openings 276 formed along the front perimeter thereof which allows the ring to pass through the openings 244 and teeth 246 on the rear of the stationary insulator 22. A pair of foldable arms 278 extend from the rear of the member 272 and are formed with a live hinge to the member 272. A locking dog 280 is formed on the inner surface of each of the arms adjacent the live hinge. The arms 278 are positioned in a plane parallel to the plane of the cylindrical member when the ring is positioned on the rear of the insulator 22. After the tongues pass through openings 244, the ring is rotated so that the tongues 274 abut the teeth 246. Then the arms are folded and the locking dogs are positioned in an opening 244 preventing further rotation of the clamp ring 26. The rear ends of the arms 278 have ridges as at 282 to facilitate securing the arms to a cable 284 formed of a plurality of the wire conductors 64 as well as provide a gripping surface to restrain the cable. A loop 286 is formed on the outer rear surface of each of the arms 278 for insertion ofa conventional Ty-Rap 290 for securing the clamp arms to the cable 284.

The boot 58 shown in cross section in FIG. 12 contains an enlarged front annular portion 292 having an inwardly extending flange 294 at the front end thereof. The boot may be secured over the cable clamp ring with the flange 294 locking the boot to the plug or re ceptacle connector body. An intermediate rearwardly tapered portion 296 of the boot extends from the front portion 292 to a rear reduced diameter serrated portion 298. The portion 298 extends beyond the rear end of the cable clamp ring and forms a seal with the conductor 284. Alternatively, as shown in FIG. 13, the boot 58 may be looped back onto the conductor 284 so that it may be clamped by means of the Ty-Rap 290 when the Ty-Rap secures the arms 278 of the ring 26 to the conductor.

Referring once again to FIG. 3, the insulator member 52 of the receptacle connector is formed of a front reduced diameter section 322, and contains a plurality of cavities 324 therethrough into which the contacts 62 are positioned as shown in FIG. 5. Each of the bores 324 contain an inwardly extending flange 326 for locking the contact 62 in the bore. The front end of the insulator section 322 contains a pair of keyways 328, 332 for insertion of the polarizing keys 116, 118 of the actuating disc 18 of the plug connector. On the outer surface of the member 322 there are formed a pair of L shaped coupling grooves 334, 336 which mate with the coupling teeth 102, 104 of the coupling ring 16. Rearward of the front section 322 is an intermediate section 342 having an outer surface 344 and a forward facing shoulder 346 formed at its junction with the front section 322. At the rear end of the portion 342 is an outwardly extending flange mounting member 348 having openings 352 therethrough for allowing the flange 348 to be permanently affixed to a piece of electrical equipment or other mounting member. The rear part of the insulator 52 is similar to the stationary insulator 22 of the plug connector and contains an enlarged bore 354 terminating in a rearward facing shoulder 356. Openings 358 extend through the insulator member so as to allow the grommet 54 to be inserted therein.

As previously pointed out, the contacts 32 and 62 of the plug and receptacle connector can be identical and each contains a contacting surface 362, 364 at the front end of the contacts, respectively. Further, locking tine members 366, 368 allow the contacts to be inserted from the rear of the insulator members and abut the forward facing shoulders of the flange 212, 326, respectively. Finally, each of the contacts terminate in a crimped barrel, 372, 374, respectively.

After the connector members are both fully assembled, the connector members are inserted with the polarizing keys I16, 118 inserted into the keyways 328 and 332, respectively. Further, a moisture seal is then formed between the insulating material 98 which is flexible due to the groove 94 formed on the surface of the coupling ring and the outer surface 344 of the insulator member 52 of the receptacle connector.

The coupling teeth 102 and 104 are inserted into the L-shaped coupling grooves 334 and 336 until they abut the forward facing shoulder 346. At this point, the position of the coupling ring 16 with respect to the disc 18 is shown in FIG. 7 (a). Further, as shown in FIG. 6 (a) the contacts are inserted with the contacting surfaces 362 and 364 of each of the contacts spaced apart and facing each other. Then the coupling ring is rotated so that the teeth 102 and 104 move in the coupling grooves. As shown in FIG. 7 (b) rotation of the coupling ring causes the driver tooth 108 to move the insulator upwardly in the direction shown by the arrow. This causes contacts 32 in the plug connector to also move upwardly as shown in FIG. 6 (b), until as shown in FIG. 6 they mate with the mating contacting surfaces of the contacts 62. At this point, the coupling teeth 102 and 104 have moved the full distance of the grooves 334 and 336. Moreover, the driver tooth 106 is against the cam shoulder surface 136. Thus, as can be readily seen, the coupling teeth 102 and 104, together with the grooves 334 and 336 assure that the contacts are separated during the mating of the connector members and that no rotation of the coupling ring occurs until the contacts are directly above each other.

Further, as can be readily seen, to separate the connectors it is necessary to once again rotate the coupling ring in the opposite direction, causing the contacts to be separated. Then the coupling teeth 102 and 104 can be removed from the L-shaped groove, separating the connector members simultaneously.

What is claimed is:

l. A low insertion force electrical connector comprising:

a first connector member having a first plurality of contacts mounted therein;

a second connector member having a second plurality of contacts for electrical connection with said first plurality of contacts subsequent to mating of said first and second connector members;

said second connector member being formed of a stationary insulator and an activating disc, said activating disc being formed with a cammed surface, said insulator having a plurality of axially alined bores for mounting of said second plurality of contacts therein; and

a shell member having a cam actuating member therein, movement of said shell member causing said cam actuating member to move with respect to said activating disc and to move said activating disc in a plane intersecting the axis of said bores wherein said first and second plurality of contacts are electrically coupled to each other.

2. An electrical connector member in accordance with claim 1 wherein said shell member further has interlocking means formed thereon, mating means formed on said first connector member, said interlocking means being movable into said mating means to a first position wherein said contacts of said connectors are positioned at a spaced apart position and further movement of said interlocking means with respect to said mating means causing said contacts to be electrically coupled to each other and simultaneously locking said connector members together.

3. An electrical connector in accordance with claim 2 wherein said mating means is formed of an L-shaped groove.

4. An electrical connector in accordance with claim 1 wherein said shell member is rotatably mounted on said stationary insulator, the rear end of said shell having a flange surface matable with a groove on said stationary insulator, and a flange member on said stationary insulator abutting said shell member flange and forming a sealing arrangement therewith.

5. An electrical connector in accordance with claim 1 wherein said cam actuating member is formed of a pair of driver teeth, shoulder members formed on said activating disc operable with respect to said driver teeth to limit movement of said teeth in a coupled and an uncoupled position of said contacts.

6. In an electrical connector, an insulator member having a bore portion, the bore portion formed with spaced openings therethrough, a grommet having outer dimensions smaller than said bore portion mounted in said bore portion and having outwardly extending por tions mounted in said spaced openings, flange members mounted on said grommet perimeter, said outwardly extending portions together with said flange members forming a tight fit with said insulator member bore portion.

7. A cable clamp ring for mounting on an insulator member having spaced apart outwardly extending portions, an inner periphery of said cable clamp ring formed of a plurality of tongues and openings, said tongues and openings being spaced for mounting said cable clamp ring on said insulator wherein tongues fit between said spaced apart portions and means for locking said clamp ring to said insulator comprising a dog lock positioned between said spaced apart portions.

8. An interfacial seal formed between a first electrical connector and a second electrical connector, said first electrical connector having a mating seal surface, and said second connector having a mating seal surface, said second connector having a front face formed in a plane perpendicular to the axis of said second connector and defining the surface of said second connector to initially be adjacent said first connector upon 3,818,420 7 8 mating of said connectors, a radial groove formed in defining a flexible sealing member movable to form a the front face of said second connector and spaced outtight seal between said connector seal surfaces when wardly from said second connector mating sea] surface, said connectors are mated. the area between said groove and mating seal surface 

1. A low insertion force electrical connector comprising: a first connector member having a first plurality of contacts mounted therein; a second connector member having a second plurality of contacts for electrical connection with said first plurality of contacts subsequent to mating of said first and second connector members; said second connector member being formed of a stationary insulator and an activating disc, said activating disc being formed with a cammed surface, said insulator having a plurality of axially alined bores for mounting of said second plurality of contacts therein; and a shell member having a cam actuating member therein, movement of said shell member causing said cam actuating member to move with respect to said activating disc and to move said activating disc in a plane intersecting the axis of said bores wherein said first and second plurality of contacts are electrically coupled to each other.
 2. An electrical connector member in accordance with claim 1 wherein said shell member further has interlocking means formed thereon, mating means formed on said first connector member, said interlocking means being movable into said mating means to a first position wherein said contacts of said connectors are positioned at a spaced apart position and further movement of said interlocking means with respect to said mating means causing said contacts to be electrically coupled to each other and simultaneously locking said connector members together.
 3. An electrical connector in accordance with claim 2 wherein said mating means is formed of an L-shaped groove.
 4. An electrical connector in accordance with claim 1 wherein said shell member is rotatably mounted on said stationary insulator, the rear end of said shell having a flange surface matable with a groove on said stationarY insulator, and a flange member on said stationary insulator abutting said shell member flange and forming a sealing arrangement therewith.
 5. An electrical connector in accordance with claim 1 wherein said cam actuating member is formed of a pair of driver teeth, shoulder members formed on said activating disc operable with respect to said driver teeth to limit movement of said teeth in a coupled and an uncoupled position of said contacts.
 6. In an electrical connector, an insulator member having a bore portion, the bore portion formed with spaced openings therethrough, a grommet having outer dimensions smaller than said bore portion mounted in said bore portion and having outwardly extending portions mounted in said spaced openings, flange members mounted on said grommet perimeter, said outwardly extending portions together with said flange members forming a tight fit with said insulator member bore portion.
 7. A cable clamp ring for mounting on an insulator member having spaced apart outwardly extending portions, an inner periphery of said cable clamp ring formed of a plurality of tongues and openings, said tongues and openings being spaced for mounting said cable clamp ring on said insulator wherein tongues fit between said spaced apart portions and means for locking said clamp ring to said insulator comprising a dog lock positioned between said spaced apart portions.
 8. An interfacial seal formed between a first electrical connector and a second electrical connector, said first electrical connector having a mating seal surface, and said second connector having a mating seal surface, said second connector having a front face formed in a plane perpendicular to the axis of said second connector and defining the surface of said second connector to initially be adjacent said first connector upon mating of said connectors, a radial groove formed in the front face of said second connector and spaced outwardly from said second connector mating seal surface, the area between said groove and mating seal surface defining a flexible sealing member movable to form a tight seal between said connector seal surfaces when said connectors are mated. 